1. Field of the Invention
The present invention relates to a method for manufacturing a semiconductor device, which comprises a step for manufacturing a wiring by a reflow method.
2. Description of the Related Art
Recently, development for a highly integrated, high speed, and miniaturized semiconductor device has been advanced. According to the miniaturization, the length of the side can be reduced to approximately 70%. However, the reduction in a longitudinal length has not realized due to keep lower resistance. Therefore, a technique to form the wiring in a narrow and deep hole that has a large aspect ratio has been required. As a metal embedded technique by which a metal material is embedded in the trench which is formed in the insulating film in advance, metal CVD or the reflow method has been developed. The reflow method is a considerably promising technique since it can be performed in lower cost.
In order to obtain a higher speed and higher efficiency, it is important that an insulating film has a lower dielectric constant, and an organic material is preferably used. However, since the organic material has lower heat resistance, it can be resolved and damaged according to the treatment temperature. In the case of forming an embedded wiring in an insulating film including an organic material, an example is that the treatment temperature is at least 20° C. lower than the heat resistant temperature of the organic material (Reference 1: Japanese Patent Laid-Open No. 10-125783). According to the method, the embedded wiring is formed after a barrier metal film is formed over the organic insulating film thereby preventing the degasification from the organic insulating film.
When using the high pressure reflow method, an attachment apparatus has become large, since equipment such as sputtering equipment and high pressure reflow equipment whose pressures are approximately 107 times different from each other are required to be connected in an inert gas or in a vacuum. Further, a manufacturing cost has been increased since it takes time to carry the substrate out or into of each the equipment.